Question about modifying GT3 (MK II) exhuast....?
08-28-2003, 07:43 PM
#1
Burning Brakes
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Question about modifying GT3 (MK II) exhuast....?
For those that have the car, how is the sound and loudness level of the stock exhuast? Differ from the MK I?
Are there any aftermarket exhuasts out there?
If so has anyone installed one?
What kind of trouble will you have with warranty issues if you modify the exhuast cat back? How much hassle will they give you?
What effect does it have on performance if any (positive? negative?)?
A friend of mine has a 993 with a custom exhuast he had made for it which has to be one of the best (if not THE best) sounding cars I've ever heard in my life. Very loud and just a sweet sweet sound when he gets on the gas. Essentially all he has is straight pipes (with baffles in them) after the cats. Wonderful!
Would this be a good move on a GT3? Why or why not? Would it hurt performance?
Are there any aftermarket exhuasts out there?
If so has anyone installed one?
What kind of trouble will you have with warranty issues if you modify the exhuast cat back? How much hassle will they give you?
What effect does it have on performance if any (positive? negative?)?
A friend of mine has a 993 with a custom exhuast he had made for it which has to be one of the best (if not THE best) sounding cars I've ever heard in my life. Very loud and just a sweet sweet sound when he gets on the gas. Essentially all he has is straight pipes (with baffles in them) after the cats. Wonderful!
Would this be a good move on a GT3? Why or why not? Would it hurt performance?
08-29-2003, 12:49 AM
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Burning Brakes
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I like the stock exhaust. It is pretty quiet at idle and low rpm, so you don't attract a lot of unwanted attention. But when you get on it and the engine comes up on the Variocam it is loud and sweet. I had the car on a dyno today and from the outside, it is really loud at 8000 rpm.
I'm sure there are or will be lots of aftermarket products out there. I doubt that any of them will add much if any performance. TPC had tested a number of aftermarket headers and most of them either do nothing or detract from performance. The same with intake system mods.
I'm not sure what you mean by modifying the exhaust from the cats back. There is nothing after the cats to modify other than the exhaust tips. If you go with after market exhaust components either headers, mufflers, and/or sport cats, the only thing you risk is the warranty on the 02 sensors and the emissions system. Of course, these are all bolt-on parts, so it's easy enought to return the car to stock for warranty work.
Unless an exhaust manufacturer can show you legitimate dyno sheets for their exhaust and will back them up with a money-back guarantee if you don't see the same improvements, I'd suggest saving your money. The Porche engineers have done a very good job with this engine and they didn't leave much on the table for the aftermarket tuners despite some of the claims that you may see out there. You aren't going to get 20 Hp by changing the exhaust.
Karl
I'm sure there are or will be lots of aftermarket products out there. I doubt that any of them will add much if any performance. TPC had tested a number of aftermarket headers and most of them either do nothing or detract from performance. The same with intake system mods.
I'm not sure what you mean by modifying the exhaust from the cats back. There is nothing after the cats to modify other than the exhaust tips. If you go with after market exhaust components either headers, mufflers, and/or sport cats, the only thing you risk is the warranty on the 02 sensors and the emissions system. Of course, these are all bolt-on parts, so it's easy enought to return the car to stock for warranty work.
Unless an exhaust manufacturer can show you legitimate dyno sheets for their exhaust and will back them up with a money-back guarantee if you don't see the same improvements, I'd suggest saving your money. The Porche engineers have done a very good job with this engine and they didn't leave much on the table for the aftermarket tuners despite some of the claims that you may see out there. You aren't going to get 20 Hp by changing the exhaust.
Karl
08-29-2003, 01:26 AM
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Burning Brakes
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Nothing after the cats except tips? In every picture of 996 exhuasts there are two mufflers, BIG ONES. Aren't these after the cats? I'm just wondering if you would have any negative effects if you just installed straight pipes in place of the mufflers but leave the cats on.
08-29-2003, 05:29 PM
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Burning Brakes
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Sure you can do muffler bypass pipes and it shouldn't affect the warranty on anything other than your bumper cover (they get real hot and can discolor the bumper cover). The car will be much louder but probably won't produce any more HP. You will save a little weight however, so it could be useful on the track. Too loud for street use IMHO.
RR, the car made 354 HP at the rear wheels. I'll be posting the dyno charts on my web site this weekend.
Karl
RR, the car made 354 HP at the rear wheels. I'll be posting the dyno charts on my web site this weekend.
Karl